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CBASE102.ARJ
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BTDELCUR.C
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1991-09-23
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/* Copyright (c) 1989 Citadel */
/* All Rights Reserved */
/* #ident "@(#)btdelcur.c 1.5 - 91/09/23" */
#include <ansi.h>
/* ansi headers */
#include <errno.h>
#ifdef AC_STDDEF
#include <stddef.h>
#endif
#ifdef AC_STDLIB
#include <stdlib.h>
#endif
#ifdef AC_STRING
#include <string.h>
#endif
/* library headers */
#include <blkio.h>
#include <bool.h>
/* local headers */
#include "btree_.h"
/*man---------------------------------------------------------------------------
NAME
btdelcur - delete current btree key
SYNOPSIS
#include <btree.h>
int btdelcur(btp)
btree_t *btp;
DESCRIPTION
The btdelcur function deletes the current key from btree btp.
The cursor is positioned to null.
btdelcur will fail if one or more of the following is true:
[EINVAL] btp is not a valid btree pointer.
[BTELOCK] btree btp is not write locked.
[BTENKEY] The cursor is null.
[BTENOPEN] btree btp is not open.
SEE ALSO
btdelete, btinsert, btsearch.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
#ifdef AC_PROTO
int btdelcur(btree_t *btp)
#else
int btdelcur(btp)
btree_t *btp;
#endif
{
int found = 0; /* key found flag */
void * key = NULL; /* key */
/* validate arguments */
if (!bt_valid(btp)) {
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(btp->flags & BTOPEN)) {
errno = BTENOPEN;
return -1;
}
/* check lock */
if (!(btp->flags & BTWRLCK)) {
errno = BTELOCK;
return -1;
}
/* check if cursor is null */
if (btcursor(btp) == NULL) {
errno = BTENKEY;
return -1;
}
/* generate search path if necessary */
if (btp->cbtnp->n < bt_ndmin(btp) + 1) {
key = calloc((size_t)1, btp->bthdr.keysize);
if (key == NULL) {
BTEPRINT;
return -1;
}
memcpy(key, bt_kykeyp(btp, btp->cbtnp, btp->cbtpos.key), btp->bthdr.keysize);
found = btsearch(btp, key);
if (found == -1) {
BTEPRINT;
free(key);
return -1;
}
free(key);
key = NULL;
if (found == 0) {
BTEPRINT;
errno = BTEPANIC;
return -1;
}
}
/* delete the current key */
if (bt_delete(btp) == -1) {
BTEPRINT;
return -1;
}
return 0;
}